EXIF Compare Utility using WPF

// <copyright file="SystemMenuItem.cs" company="Nish Sivakumar">
// Copyright (c) Nish Sivakumar. All rights reserved.
// </copyright>

namespace NS.MVVM
{
    using System.Windows;
    using System.Windows.Input;

    public class SystemMenuItem : Freezable
    {
        public static readonly DependencyProperty CommandProperty = DependencyProperty.Register(
            "Command", typeof(ICommand), typeof(SystemMenuItem), new PropertyMetadata(new PropertyChangedCallback(OnCommandChanged)));

        public static readonly DependencyProperty CommandParameterProperty = DependencyProperty.Register(
            "CommandParameter", typeof(object), typeof(SystemMenuItem));

        public static readonly DependencyProperty HeaderProperty = DependencyProperty.Register(
            "Header", typeof(string), typeof(SystemMenuItem));

        public static readonly DependencyProperty IdProperty = DependencyProperty.Register(
            "Id", typeof(int), typeof(SystemMenuItem));

        public ICommand Command
        {
            get
            {
                return (ICommand)this.GetValue(CommandProperty);
            }

            set
            {
                this.SetValue(CommandProperty, value);
            }
        }

        public object CommandParameter
        {
            get
            {
                return GetValue(CommandParameterProperty);
            }

            set
            {
                SetValue(CommandParameterProperty, value);
            }
        }

        public string Header
        {
            get
            {
                return (string)GetValue(HeaderProperty);
            }

            set
            {
                SetValue(HeaderProperty, value);
            }
        }

        public int Id
        {
            get
            {
                return (int)GetValue(IdProperty);
            }

            set
            {
                SetValue(IdProperty, value);
            }
        }

        protected override Freezable CreateInstanceCore()
        {
            return new SystemMenuItem();
        }

        private static void OnCommandChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            SystemMenuItem systemMenuItem = d as SystemMenuItem;

            if (systemMenuItem != null)
            {
                if (e.NewValue != null)
                {
                    systemMenuItem.Command = e.NewValue as ICommand;
                }
            }
        }
    }
}